Recommit [llvm-debuginfo-analyzer] (02/09) - Driver and documentation

Originally committed in fe7a3ced

Reverted in 26dd64ba

Buildbot failures:
https://lab.llvm.org/buildbot#builders/139/builds/29663
- unittest trigger an invalid assertion.

https://lab.llvm.org/buildbot#builders/196/builds/19665
- 'has virtual functions but non-virtual destructor' warning as error.

Recommitted with fix:
- Removed the assertion.
- Added virtual destructor.